Full Coverage when Expecting an Exception

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In JUnit 4 we might write the following:

@Test(expected=RuntimeException.class)
public void methodThatWeExpectAnException() {
    throw new RuntimeException();
}

This test will pass. Yes it's trivial, of course it would pass. (In reality the single line of code would instead send a message to some object that ultimately would need to generate a RuntimeException for a "real" test to pass.) Fine. That's not the point.

So what's the problem with this? Nothing, except that some coverage tools will report the last "line" (the close curly-brace) as not being covered since we did not exit the method cleanly.

Here's a way to rewrite the above test so that you can assure coverage:

@Test
public void methodThatWeExpectWillThrowAnException() {
    boolean expectedThrown = false;
 
    try {
        throw new RuntimeException();
    } catch (RuntimeException e) {
        expectedThrown = true;
    }
 
    assertTrue(expectedThrown);
}

This version is a bit longer, isn't it?

Here are some comments I'd like to hear from you:

• Is it any better?
• Does is express our intent any better?
• Isn't it just silly to run coverage tools on your test code?
• Is anybody having Pascal flashbacks? (If you don't get this question...you poor &*$^@~).

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